If you download music to a specific, or multiple folders on your computer,
Musicmatch
Checking the box next to Enable WatchFolders will scan your WatchFolder every time the Jukebox is opened. This may impact the performance of other applications while scanning.
The Jukebox must be open at the time you add new tracks to your "watched" folder or they may not be added to your Library automatically. If the jukebox was closed, click the Check WatchFolders now button to scan your folder for tracks added.
Go to the menu File/WatchFolders
Check the box next to Enable WatchFolders
Click the Add button and browse for the folder(s) where you download new music to. Select the folder(s) and click OK.
WatchFolders will now monitor those folders and add new additions to your Music Library.